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 A185622 Column 2 of triangular matrix T = A185620, which satisfies: T^3 - T^2 + I = SHIFT_LEFT(T). 3
 1, 1, 5, 27, 173, 1330, 12134, 129359, 1587501, 22127494, 346245249, 6021401618, 115373290404, 2417393483696, 55028734386699, 1353170738090204, 35764709876549353, 1011496211524329699, 30490289594142366215 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS PROG (PARI) {A185620(n, k)=local(A=Mat(1), B); for(m=1, n, B=A^3-A^2+A^0; A=matrix(m+1, m+1); for(i=1, m+1, for(j=1, i, if(i<2|j==i, A[i, j]=1, if(j==1, A[i, j]=1, A[i, j]=B[i-1, j-1]))))); return(A[n+1, k+1])} /* Column 2: */ {a(n)=A185620(n+2, 2)} CROSSREFS Cf. A185620, A185621, A185623. Sequence in context: A109963 A201870 A091101 * A225309 A231091 A205774 Adjacent sequences:  A185619 A185620 A185621 * A185623 A185624 A185625 KEYWORD nonn AUTHOR Paul D. Hanna, Feb 01 2011 STATUS approved

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Last modified December 5 12:51 EST 2020. Contains 338947 sequences. (Running on oeis4.)